Internal-combustion engine



"6.4. RATHBUN INTERNAL COMBUSTI ON ENGI NE Filed Jan. 28. 1928 45heets-She9t l INQQENTOR. e If Raf/112202 vH15 ATT;%EY.

Feb. :25, 1930,

G. J. RATHBUN INTERNAL COMBUSTION ENGINE Filed Jan. 28. 1928 4 sheet-shem f. A M K a e. ad .0. v.

Y I INVENTOR. 1 ezlllafhhul;

- HIS/4T ORNEY.

Patented Feb, 25, 1930 UNITED STATES PATENT OFFICE GEORGE J. RATHIBUN, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL RAND COMPANY, OF JERSEY CIT Y, NEW JERSEY, A CORPORATION OF NEW JERSEY, AND THE RATHBUNJONES ENGINEERING COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO INTERNAL-COMBUSTION ENGINE This invention relates to internal combustion engines, and more particularly to apparatus to be used in combination therewith for starting such engines. In most instances by injecting motive fluid, such as compressed air, successively into the cylinders so as to 7 get them into motion sufficiently so that the fuel charge will be thereafter automatically compressed andignited. -'-In case of engines having less than four cylindersand operating .on a four' stroke cycle,'.the're' are found dead spots or'pe'riods of no. pressure at which the engine is likely to stop or will not start-from compressedairin'ected into the cylinder,

It is an-objecto this inrentipu toeliminate such .deadspots by converting the engine temporarily from fourgto two stroke cyclop} eration. v Another object-ofthe" ntion is to enable the engine to be startedby compressed air in either direction of rotationof the crank shaft atthe will of the operator. Still another object ofthe invention is to improve andsimpli-fy the apparatusfor-starting or for reversing the direction of rotation'of the comb'ustionengine. v 1 i c Other objects and advantages of the invention will be in part obvious and in part pointed out hereinafter;

Inthe drawings forming part of. the speci fication and in which similar reference characters refer to similar parts,

Figure 1 is a side elevation of an engine.

constructed inaccordance with the practice of the invention, part of the crankcase being broken away to show the operating connections for driving the crank shaft, the valve push rods and the starting controlling mechanism, t Figure 2 is a vertical cross section of the ,engine showing more particularly. the valve operating mechanism and'meansfor rendering such mechanism inoperative,

Figure 3 is a vertical section through the starting and reversing control mechanism,

Figure 4 is across section through the starting and reversing control mechanism taken along the line 44 of Figure 3 looking in the direction of the arrows,

also be provided with Figure 5 is a cross section through the starting and reversing control mechanism taken along the line 5-5 of Figure 3 looking in the direction of the arrows, and 5 large internal'combustion engines are started Figure 6 is a longitudinalsection through the starting and reversing control mechanism taken along the line 6-6 of Figure 3 looking in the direction of :the arrows.

' Referring to the drawings and more particularly to Figures 1 and 2, the internal combustion engine as shown comprises a plu rality of cylinders A of which three are shown each having aipistonB adapted to reciprocate therein and provided with a connecting rod C operatively connected to crank pins D for rotating a suitable crank shaft. E. Each cylinder A is also provided with a combustion chamberflF formed by a block G and a head H within which is mounteda pair of valves J preferably of the poppet type and normally held to their seats by a spring K. The cylinders A arepre'ferably water. jacketed being provided with a space L for cooling fluid and, if desired, the block G and head H may cooling water spaces 0 and P respectively;

The valves J are arranged to be operated or depressed by rocker arms Q actuated by push rods R operatively connected with a countcrshaft S having eccentrics Tand eccentric followers U connected with the push rods R. Preferably the eccentric followers U are connected by means of a crank in V to a plunger slidable in a bushing in the frame of the engine baseY.

In the normal operation of the engine on a four stroke cycle, each valve J is adapted to be unseated once for every two revolutions of the crank shaft E and accordingly the countershaft is driven at one half the crank shaft speed. Due to the eccentric connections, above described, between the push rods R and the countershaft S, the motion of the push rods is continuous and since the valves J must be operated for only a small portionof the piston stroke, the rocker arm Q, is-provided with a bearing fulcrum abutment Z mounted which may be of the form well known in a coil spring 6.

cycle operation to a two stroke cycle, it is desirable that the valve J which is used for admission should be held closed. The exhaust from the cylinder A in this mode of operation is taken care of by an exhaust port I) located in the wall of the cylinder A- to be uncovered by the piston near the end of its downward stroke. On alternate upward strokes of the pistons B the exhaust is taken care of in the usual manner by the normally operating valve-J. During the starting period, the speed of the engine, is relatively slow and the pressure fluid may be easily taken care of through the exhaust port 5. The compression on the upward stroke of the piston B with both valves J closed is not. comparable as a retarding force to the pressure tending to force another one of the pistons down so that the rotation is kept continuous.

During two cycle operation of the engine, as as been said, one of the valves J, which would normally operate as an admission valve, is kept closed. To this end means is provided comprising a cylinder 0 having a piston (Z therewithin normally depressed by Beneath the piston d, (ompressed air or other fluid under pressure is adapted to be injected, there being provided an aperture f and a pipe connection g there for through which such pressure fluid may enter the cylinder under thepiston (Z. A plunger h preferably carried by the piston d is adapted to extend through a head j of the cylinder 0 to bear against a free end of the abutment Z whichis pivoted at its opposite end as at In. The plunger h preferably extends entirely through the cylinder 0 and carries a collar h adapted to abut the upper end wall of the cylinder 0 to limit the travel of the piston (Z in an upwardly direc-" tion. 'Both the cylinder 0 and the pivot are mounted on a bracket 0 supported by I the head H. The abutment Z is provided 45' with an upwardly extending arm 1) and a spring. 9 interposed between the arm p and the cylinder 0 to cause said abutment Z to "follow the movement of the plunger rod h.

Thus, if the piston d rises, the abutment Z swings upwardly out of the path of the rocker Q and the valve J is accordingly not deling the operation of the piston d and for injecting air at the proper timing through the air injectionnozzle 1- to the interior of the cylinders A and is indicated in Figure 1 generally at u. Details of the mechanism a are shown in Figures 3, 4,5 and-6 and include a box 4) within which is provided a shaft '10 driven by gears m and y at the speed of rotation of the crank shaft E. As shown in cams 2 and 3 is operated, the other is mop-- erative. The three cams 2 in this instance are set at 120 angular difference on the shaft to to correspond with the setting of the crank pins D of the crank shaft E. Likewise, the cams 3 are set at 120 intervals on the shaft w.

The cams 2 are adapted cooperate a set of valves 4 of the poppet type, there being provided for each cam 2 arocker arm 5 having a cam following roller 6 and an adjustable valve tappet 7 The rocker arms 5 are pivotally mounted on a shaft 8. Likewise the cams 3 are adapted to actuate rocker arms 9 having cam following rollers 10 and adj ustable tappets 11 for actuating poppet valves 12 similar to the valves 4. The valves 4 are adapted to control the flow of motive fluid and to time the same to the air injection nozzles r for forward runnlng of the engine.

For reverse running of the engine, the valves,

' leading from a suitable source of pressure fluid (not shown). Each pair of controlling valves 4 and 12 are adapted to seat in apertures 17 and 18 respectively and-control the flow of motive fluid through these apertures from the chamber 14 to inner chambers 20 leading by means of the pipe connections't to each cylinder A.. A separate chamber 20 is provided for eachof the cylinders A. As the valves 4 and 12 lift, therefore, the compressed air is fed from th'e chamber 14 into the chamber 20 and thence by wayof the pipe connection t to the air injection nozzle 1'.

Means is provided by which the rocker arms 5 and 9 may be shifted so as to operate neither of the valves 4 and 12 or to operate the valves 4 and not the valves 12 or to operate the valves 12 and not the valves 4. To this end the shaft 8, upon which the rocker arms are mounted, is provided with an eccentric hearing in the walls of the box '0. The center of the shaft bearings 21 is off-set from the center'of the eccentric bearing portion 22 of the shaft 8, thecenter of the bearing portion 22 being shown at 23. The-upper end of the bearing portion 24 of the shaft 8 preferably extends beyond. the end wall 25 of the box '0 and is provided with a manually operable crank handle 26 by which the operator may turn the shaft 8.

As the shaft 8 is rotated in a clockwise direction (Figure 5), the rocker arms 5 and 9 are broughtinto position so that the rocker arm 9 is adapted to be engaged by the cam 3 for operating the valve 12. When the crank 26 and the shaft 8 are turned in the opposite direction, the rocker arms are moved to a position by'means of the eccentric bearing portion 22 in which the cam 2 engages the rocker arm 5 to actuate the valves 4'. In the intermediate position of the crank 26, both sets of rocker arms 5 and 9 are carried out-of engagement with the cams 3 and 2 and accordingly neither of the set of valves 4 and 12 are operated. The last is the normal running upon movement of the shaft 8 is adapted to engage oneor the other of a pair of valve lifters 28 and 29. The valve lifter 28 is adapted to raise from itsseat a tappet valve 30 controlling an aperture 31 leading from the chamber 14 to an inner chamber 32 lead ing by means of the pipe 9 to the cylinder 0 whereby the one set of valves J is controlled. That set includes one of the valves J of each cylinder A, the remaining valves J are controlled by a tappet valve'33 controlling an aperture 34 leading from the chamber 14 to .an inner chamber 35 and thence through a pipe connection g to the remaining cylinders .0. The tappet valve 33 is adapted to be actuated by the valve lifter 29. In the intermediate position of the handle 26, neither the valve 30 nor the valve 33 are lifted from their seats and in this position'accordingly none of the-pistons d in the cylinders c'are operated. Rotation of the crank26 in a clockwisedirection from the intermediate position will'cause the cam' 27 to operate the valve lifter 29 lifting the'valve 33 to permit compressed air to flow to the cylinders 0' operating one set of the valves J- and simultaneously throw the rocker arms 9 into position to be engaged by the cams 2 whereupon the compressed air is fed to the cylinders in time to produce forward rotation ofthecrank shaft E. ,Simi larly, turning of the crank handle 26 in a counterclockwise direction will cause operation of the other valves J and operation of the valves 12 bythe'rock'er arms 9 to produce airinjection at the nozzles r to cause reverse rotation of the-crank shaft 'E.

' The valve lifters 28 and 29 may be of any 5 suitable form. They are preferably mounted on a single pivot (Figure 4) The valves 30 and 33 are normally held to their seats and whei in operation are returned to their seats by suitable coil springs 37 interposed between the valve heads and the cover member 15.

Likewise, the valves 4 and 12 are normally held to their seats by a suitable coil spring 38 interposed between the cover member 15 andthe valveheads. r 1

- Ifdesircd, the shaft 'w may be provided with anti-friction bearings as shown at 39 and extending into the box a is preferably rigid and does not need a. bearing. The end 440 of the shaft 8 may be relatively small and journalled in the wall of the box a at an aperture 41.

The operation of the engine is as follows: If the operator desires the engine to operate in a forward direction, he turns the handle in a clockwise direction to its extreme position. The shaft 8 is rotated thereby to cause the valve lifter 29 to raise the valve 33 thereby'a'dmitting compressed air from the supply pipe 16 and the chamber 14 past the valve into the inner chamber 35. Compressed air therefor is fed through the pipe connection 9' to the cylinders c at the right of veach cylinder (Figure 1) causing the corresponding pistons d to be raised against the strength of the spring e and lifting the rocker abutment 'Z out of the path of the rocker arm Q so that the free end of the abutment lies against the bottom of the cylinder 0 thereby throwing the corresponding valves J out of action.

These valves J which are thrown out of action would have been the admission valves for forward rotation of the crank shaft E. At the same time, the rocker arms 5 are moved over between the shaft 8 so that the cams 2 are adapted to cause the rocker arms 5 to 'operatethe valves 4 upon rotation of the shaft to.

'If there are three cylinders A, one of the cams 2 will always be in position to raise one of the valves 4 and compressed air will therefore pass from the chamber 14 into one of the chambers 20 and thence by way of one injection nozzles 1-. The air pressure thus admitted causes the piston B to be depressed grotating the crank shaft E in a forward direction. The admission valves J will remain closed since the corresponding poppet valve 33 remains in open position. The valves 4 however operate successively to cause admission of compressed air in the various cylinders A for down strokes of the pistons 13..

At the end of the downward stroke of the pistons B, the air actuating those pistons is exhausted through the exhaust ports 6. Exhaust will also take place as usual on alternat ing up strokes of the pistons B due to half of the valves operating as usual being unaffected by the controlling mechanism. On the remaining up strokes of the pistons B,

some compression will take place as usual but .of'the pipe connections t to one of the air as -can be understood, this back pressure will not be suflicient to counterbalance the full pressure of the air adm'itted'in other cylinders A.

If the engine is of the solid fuel injection type as in this instance, fuel injection will take place as usual at the fuel injection nozzle 42 and after several rotations of the crank shaft E, explosions will take place as usual. The engine having been started, the operator returns the crank 26 to its neutral position thereby shutting off the supply of compressed or starti air to the cylinders c andA and permitti g the pistons 01 to return the abutment Z. The rocker arms Q Will then cause the normal operation of the valves J.

To start the operation of the engine in the reverse direction, the operator turns the handle 26 in an anti-clockwise direction (Figure 4) which causes operation of the poppet valve 80. Compressed air is .fed to the pipe connection 9 to the left hand cylinder 0 of each cylinder A (Figure 1) causing the corresponding valves J to be rendered inoperative. Likewise, the valves 12 are operated to cause timed air admission at the air injection nozzle 1" for reversing the direction of rotation of the crank shaft-E. I

Thus by the above construction are accomplished among others the objects hereinbefore referred to.

cycle operation, and means for controlling the I claim: 1. An mternal combustlon engine compr1s ing a plurality of cylinders, pistons adapted to reciprocate therein, a pair of valves for each cylinder, means for opening said valves during'the normal operation of the engine, pressure actuated means associated with each valve, for selectively rendering either of said opening means ineffective during the complete cycle of piston operation to change the engine from four stroke to two stroke per admission of pressure fluid to the pressure actuated means.

2. An internal combustion engine comprising a plurality of cylinders, pistons adapted to reciprocate therein, a pair of valves for each cylinder, means for opening said valves during the normal operation of the engine, pressure actuated means associated with each valve for selectively rendering ineffective the opening means associated'with either one of each pair of valves during the complete cycle associated with each valve for rendering said opening means ineffective during the C0111- plete cycle of piston operation to change the engine from four stroke to two stroke per cycle operation, including cylinder and piston elements, and manually controlled means for selectively admitting pressure fluid to the cylinder elements to actuate the piston elements to inoperative positions.

4. An internal combustion engine comprising a plurality of cylinders, pistons adapted to reciprocate therein, a pair of admission and exhaust valves for each cylinder, means for opening said valves, pressure actuated means for rendering said opening means inoperative during the complete cycle of piston operation to change the engine from four stroke to two stroke per cycle operation, ineluding. cylinder and piston elements associated with each valve, said piston element being pneumatically actuated to inoperative position, connections to each cylinder element to supply motive fluid thereto, mechanically actuated valve means for controlling the admission of pressure fluid to the connections, and manually actuated means for rendering said valve means effective.

5. An internal combustion engine compris- 1 ing a plurality ofmain cylinders, pistons adapted to reciprocatetherein, a pair of admission and exhaust valves for each said main cylinder, means for normally opening said admission and exhaust valves, and pressure actuated means associated with each valve for controlling the operation of said opening means.

6. An internal combustion engine comprising a plurality of main cylinders, pistons adapted to reciprocatein said cylinders, air admission nozzles in said cylinders, a pair of admission and exhaust valves for each of said cylinders, means for normally opening said admission and exhaust valves, and manually controlled centralized means for rendering the opening'means of one of each pair of valves inoperative and for admitting compressed air to all of the admission nozzles.

7. An internal combustion engine comprising a plurality of main cylinders, pistons adapted to reciprocate therein, a pair of ad-= mission and exhaust valves for each said main cylinder, means for normally opening said valves, pneumatic means for rendering the opening means of one of each pair of valves inoperative, a nozzle for 'each cylinder for admitting compressed air to depress said pistons, and manually. controlled centralized means to admit compressed air to all the nozzles and-t0 selectively control said means for rendering said opening means inoperative.

8. An internal combustion engine comprising a plurality of main cylinders, pistons adapted to reciprocate in said cylinders, a pairof admission and exhaust valves for each said cylinder, means for normally opening said admission and exhaust valves, in-

eluding a rocker arm,- a movable abutment cooperative with said rocker arm, pressure actuated means individual to each valve to efiect movement of. said abutm'ent into and out of the path of the opening means, and manually controlled valve means for controlling the admission of pressure fluid to the pressure actuated means.

9. "An internal combustion engine comprismg a plurality of main cyllnders, plstons adapted to reciprocate insald cylinders, a.

pair of admission and exhaust valves for each said cylinder, means for normally opening saidadmission and exhaust valves',,ineluding a rocker arm, a movable abutment cooperative with said rocker arm,'means associated with each valve comprising a second cylinder and a second piston in said second cylinder, manually controlled means to control the admission of compressed air to said second cylinders to release said abutment,

spring operative means to normally hold said abutment in the path of the rocker arm, and

means to control admission of compressed air to said second cylinder to release said abutment.

"In testimony whereof I have signed this specification.

Y 1 GEORGE J. RATHBUN. 

